Depending on the processed material from each drill must be properly sharpened. To verify the correct angle will help a specially prepared square plate of copper or aluminium with a thickness of 1 mm.
To become operational protractor enough to cut it cut, as shown in the picture: a large cutout at an angle of 120 degrees, the other half is 60 degrees and the surviving corner of a square is 90.
Recommend to read
A BOAT FOR EVERY TASTE
In which only the terms will not be during the journey of the lovers of water tourism! And not always the boat suitable for sailing in a pond, suitable for another. We have...
WITH A SAIL IN HAND
SKIING. You can go sailing on skis, not installing them on the mast (see "M-K", 1982, № 12), but simply holding it in his hands behind him. This sail has a diamond shape, stretched on...